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| -rw-r--r-- | MODULE_LICENSE_FRAUNHOFER | 0 | ||||
| -rw-r--r-- | Makefile.am | 1 | ||||
| -rw-r--r-- | README.md | 95 |
3 files changed, 60 insertions, 36 deletions
diff --git a/MODULE_LICENSE_FRAUNHOFER b/MODULE_LICENSE_FRAUNHOFER deleted file mode 100644 index e69de29..0000000 --- a/MODULE_LICENSE_FRAUNHOFER +++ /dev/null diff --git a/Makefile.am b/Makefile.am index 767b5f7..9e2e164 100644 --- a/Makefile.am +++ b/Makefile.am @@ -213,6 +213,7 @@ libfdk_aac_la_SOURCES = \ EXTRA_DIST = \ $(top_srcdir)/bootstrap \ $(top_srcdir)/NOTICE \ + $(top_srcdir)/README.md \ $(top_srcdir)/Android.mk \ $(top_srcdir)/fdk-aac.sym \ $(top_srcdir)/documentation/*.pdf \ @@ -1,34 +1,32 @@ -fdk-aac-dabplus -=============== +fdk-aac-dabplus Package +======================= -A standalone library of the Fraunhofer FDK AAC code from Android, patched for -960-transform. Used for DAB+ broadcast encoding. +This package contains several tools that use the standalone library +of the Fraunhofer FDK AAC code from Android, patched for +960-transform to do DAB+ broadcast encoding. -Also includes a version with a ODR-DabMux compatible ZeroMQ output. +The first tool, *dabplus-enc-file* can encode from a file or pipe +source, and encode into a file or pipe. There is no PAD support. -There is experimental support for DAB MOT Slideshow and DLS, written by -CSP http://rd.csp.it +The *dabplus-enc-file-zmq* can encode from a file or pipe source, +and encode to a ZeroMQ output compatible with ODR-DabMux. +The *dabplus-enc-alsa-zmq* can encode from an ALSA soundcard, +and encode to a ZeroMQ output compatible with ODR-DabMux. It supports +experimental sound card clock drift compensation, that can compensate +for imprecise sound card clocks. -Usage: +*dabplus-enc-file-zmq* and *dabplus-enc-alsa-zmq* include experimental +support for DAB MOT Slideshow and DLS, written by [CSP](http://rd.csp.it). - aac-enc-dabplus [OPTION...] - - -b, --bitrate={ 8, 16, ..., 192 } Output bitrate in kbps. Must be multiple of 8. - -i, --input=FILENAME Input filename (default: stdin). - -o, --output=FILENAME Output filename (default: stdout). - -a, --afterburner Turn on AAC encoder quality increaser. - -f, --format={ wav, raw } Set input file format (default: wav). - -c, --channels={ 1, 2 } Nb of input channels for raw input (default: 2). - -r, --rate={ 32000, 48000 } Sample rate for raw input (default: 48000). +To encode DLS and Slideshow data, the *mot-encoder* tool reads images +from a folder, and DLS text from a file, and generates the PAD data +for the encoder. +For detailed usage, see the usage screen of the different tools. -The encoder with ZeroMQ output has the same options as above, -but takes a zmq destination url as output - -See - aac-enc-dabplus-zmq -h - +More information is available on the +[Opendigitalradio wiki](http://opendigitalradio.org) How to build ============= @@ -40,50 +38,75 @@ Requirements: * Download code and unpack it. * Download and install libfec from https://github.com/Opendigitalradio/ka9q-fec * do "./configure", then "make" and "make install" -* use aac-enc-dabplus or aac-enc-dabplus-zmq to encode live stream or file. +* See the possible scenarios below on how to use the tools * use mot-encoder to encode images into MOT Slideshow How to use ========== +We assume: + + ALSASRC="default" + DST="tcp://yourserver:9000" + BITRATE=64 + Scenario 1 ---------- +Live Stream from ALSA sound card at 32kHz, with ZMQ output for ODR-DabMux: + + dabplus-enc-alsa-zmq -d $ALSASRC -c 2 -r 32000 -b $BITRATE -o $DST + +To enable sound card drift compensation, add the option **-D**: + + dabplus-enc-alsa-zmq -d $ALSASRC -c 2 -r 32000 -b $BITRATE -o $DST -D + +You might see **U** and **O<number>** appearing on the terminal. They correspond +to audio underruns and overruns that happen due to the different speeds at which +the audio is captured from the soundcard, and encoded into HE-AACv2. + +High occurrence of these will lead to audible artifacts. + + +Scenario 2 +---------- Live Stream encoding and preparing for DAB muxer, with ZMQ output, at 32kHz, using sox. +This illustrates the fifo input of *dabplus-enc-file-zmq*. - ALSASRC="default" - DST="tcp://yourserver:9000" - BITRATE=64 sox -t alsa $ALSASRC -b 16 -t raw - rate 32k channels 2 | \ - ../fdk-aac-dabplus/aac-enc-dabplus-zmq -r 32000 \ + dabplus-enc-file-zmq -r 32000 \ -i /dev/stdin -b $BITRATE -f raw -a -o $DST -p 4 -Scenario 2 + +Scenario 3 ---------- Live Stream encoding and preparing for DAB muxer, with FIFO to odr-dabmux, 48kHz, using arecord. arecord -t raw -f S16_LE -c 2 -r 48000 -D plughw:CARD=Loopback,DEV=0,SUBDEV=0 | \ - aac-enc-dabplus -b 24 -f raw -c 2 -r 48000 -i /dev/stdin -o /dev/stdout 2>/dev/null | \ + dabplus-enc-file -a -b 24 -f raw -c 2 -r 48000 -i /dev/stdin -o /dev/stdout 2>/dev/null | \ mbuffer -q -m 10k -P 100 -s 360 > station1.fifo +Here we are also using the ALSA plughw feature. -Scenario 3 +Scenario 4 ---------- Wave file encoding, for non-realtime processing - aac-enc-dabplus -a -b 64 -i wave_file.wav -o station1.dabp + dabplus-enc-file -a -b 64 -i wave_file.wav -o station1.dabp + Usage of MOT Slideshow ====================== -MOT Slideshow is an experimental feature. The mot-encoder reads images in the specified folder, -and generates the PAD data for the encoder. This is communicated through a unique fifo in /tmp, -therefore only one instance can run on a single machine. +MOT Slideshow is an experimental feature. The *mot-encoder* reads images from +the specified folder, and generates the PAD data for the encoder. This is +communicated through a fifo to the encoder. -Only aac-enc-dabplus-zmq inserts the PAD data from mot-encoder into the bitstream. +Only *dabplus-enc-file-zmq* and *dabplus-enc-alsa-zmq* insert the PAD data from +mot-encoder into the bitstream. This is an ongoing development. |